engine/search.h

Search algorithms and transposition table.

Typedefs

using SearchInfoHook = std::function<void(const SearchIteration&)>

Functions

void clearTranspositionTable()

int getHashFull()

Table occupancy in permille, for the UCI hashfull info field.

Sampled over the first 1000 entries rather than swept, per the usual convention — the field is reported every iteration and must not cost a pass over the table.

int readHashEntry(int alpha, int beta, int depth)

void recordHash(int score, int depth, int hashFlag, int move)

int scoreMove(int move, int hashMove)

void scoreMoveList(moves *moveList, int *moveScores)

void pickMove(moves *moveList, int *moveScores, int index)

int staticExchangeEvaluation(int move)

void setUseSEE(bool enabled)

bool getUseSEE()

void setUseSEEOrdering(bool enabled)

bool getUseSEEOrdering()

void setUseSEEPruning(bool enabled)

bool getUseSEEPruning()

void setUsePVS(bool enabled)

bool getUsePVS()

void setUseNullMovePruning(bool enabled)

bool getUseNullMovePruning()

void setUseLMR(bool enabled)

bool getUseLMR()

void setUseFutilityPruning(bool enabled)

bool getUseFutilityPruning()

void setUseSingularExtensions(bool enabled)

bool getUseSingularExtensions()

void setUseProbCut(bool enabled)

bool getUseProbCut()

void setUseInternalIterativeDeepening(bool enabled)

bool getUseInternalIterativeDeepening()

void setUseAspirationWindows(bool enabled)

bool getUseAspirationWindows()

void setUseHistoryOrdering(bool enabled)

bool getUseHistoryOrdering()

void setUseContinuationHistory(bool enabled)

bool getUseContinuationHistory()

void setFutilityMargin(int depth, int centipawns)

int getFutilityMargin(int depth)

void setProbCutMargin(int centipawns)

int getProbCutMargin()

void setSingularMarginPerDepth(int centipawns)

int getSingularMarginPerDepth()

void setLmrBaseHundredths(int hundredths)

int getLmrBaseHundredths()

void setLmrDivisorHundredths(int hundredths)

int getLmrDivisorHundredths()

void setHashMegabytes(int megabytes)

int getHashMegabytes()

int getMaxHashMegabytes()

int getActiveHashEntries()

void sortMoves(moves *moveList)

void enablePvScoring(moves *moveList)

int isRepeating()

int repetitionCount()

bool isMateScore(int score)

std::optional<int> mateDistanceIn(int score)

void setSearchInfoHook(SearchInfoHook hook)

int quiescence(int alpha, int beta)

int negamax(int alpha, int beta, int depth)

void searchPosition(int depth)

void printMoveScores(moves *moveList)

Variables

tt transpositionTable[hashSize]

int killerMoves[2][maxPly]

int historyMoves[12][64]

int pvLength[maxPly]

int pvTable[maxPly][maxPly]

int followPV

int scorePV

int bestMove

int mvvLVA[12][12]

int skillLevel

struct SearchIteration

#include <search.h>

Public Members

int depth = 0

int scoreCp = 0

long nodes = 0

long long timeMs = 0

const int *pv = nullptr

int pvLength = 0